From 2ab4d4188670356dcb82a80f2fc4598f5145c77d Mon Sep 17 00:00:00 2001

From: Jan Friesse <jfriesse@redhat.com>

Date: Thu, 10 Jan 2019 15:06:20 +0100

Subject: [PATCH] totemip: Use AF_UNSPEC for ipv4-6 and ipv6-4

AF_UNSPEC returns different results than AF_INET/AF_INET6, because of

nsswitch.conf search is in order and it stops asking other

modules once current module success.

Example of difference between previous and new code when ipv6-4 is used:

- /etc/hosts contains test_name with an ipv4

- previous code called AF_INET6 where /etc/hosts failed so other methods

were used which may return IPv6 addr -> result was ether fail or IPv6

address.

- new code calls AF_UNSPEC returning IPv4 defined in /etc/hosts ->

result is IPv4 address

New code behavior should solve problems caused by nss-myhostname.

Signed-off-by: Jan Friesse <jfriesse@redhat.com>

Reviewed-by: Fabio M. Di Nitto <fdinitto@redhat.com>

---

 exec/totemip.c                   |  106 +++++++++++++++++++++++++++-----------

 include/corosync/totem/totemip.h |    6 +-

 man/corosync.conf.5              |    8 ++-

 3 files changed, 83 insertions(+), 37 deletions(-)

diff --git a/exec/totemip.c b/exec/totemip.c

index 9d96e1b..36d0a72 100644

--- a/exec/totemip.c

+++ b/exec/totemip.c

@@ -1,5 +1,5 @@

 /*

- * Copyright (c) 2005-2011 Red Hat, Inc.

+ * Copyright (c) 2005-2019 Red Hat, Inc.

  *

  * All rights reserved.

  *

@@ -288,69 +288,113 @@ int totemip_parse(struct totem_ip_address *totemip, const char *addr,

     enum totem_ip_version_enum ip_version)

 {

 	struct addrinfo *ainfo;

+	struct addrinfo *ainfo_iter;

+	struct addrinfo *ainfo_ipv4;

+	struct addrinfo *ainfo_ipv6;

+	struct addrinfo *ainfo_final;

 	struct addrinfo ahints;

 	struct sockaddr_in *sa;

 	struct sockaddr_in6 *sa6;

 	int ret;

 	int debug_ip_family;

-	int ai_family1, ai_family2;

+	int ai_family;

 	memset(&ahints, 0, sizeof(ahints));

 	ahints.ai_socktype = SOCK_DGRAM;

 	ahints.ai_protocol = IPPROTO_UDP;

-	ai_family1 = ai_family2 = -1;

+	ai_family = AF_UNSPEC;

+	debug_ip_family = 0;

 	switch (ip_version) {

 	case TOTEM_IP_VERSION_4:

-		ai_family1 = AF_INET;

+		ai_family = AF_INET;

+		debug_ip_family = 4;

 		break;

 	case TOTEM_IP_VERSION_6:

-		ai_family1 = AF_INET6;

-		break;

-	case TOTEM_IP_VERSION_4_6:

-		ai_family1 = AF_INET;

-		ai_family2 = AF_INET6;

+		ai_family = AF_INET6;

+		debug_ip_family = 6;

 		break;

 	case TOTEM_IP_VERSION_6_4:

-		ai_family1 = AF_INET6;

-		ai_family2 = AF_INET;

+	case TOTEM_IP_VERSION_4_6:

+		/*

+		 * ai_family and debug_ip_family are already set correctly

+		 */

 		break;

 	}

-	ahints.ai_family = ai_family1;

+	ahints.ai_family = ai_family;

+

 	ret = getaddrinfo(addr, NULL, &ahints, &ainfo);

-	if (ret && ai_family2 != -1) {

-		ahints.ai_family = ai_family2;

-		ret = getaddrinfo(addr, NULL, &ahints, &ainfo);

-	}

-	debug_ip_family = 4;

-	if (ahints.ai_family == AF_INET6) {

-		debug_ip_family = 6;

-	}

+	if (ret == 0 && ai_family == AF_UNSPEC) {

+		ainfo_ipv4 = ainfo_ipv6 = NULL;

-	if (ret) {

-		log_printf (LOGSYS_LEVEL_DEBUG, "totemip_parse: IPv%u address of %s not resolvable",

-		    debug_ip_family, addr);

+		/*

+		 * Walk thru results and store first AF_INET and AF_INET6

+		 */

+		for (ainfo_iter = ainfo; ainfo_iter != NULL; ainfo_iter = ainfo_iter->ai_next) {

+			if (ainfo_iter->ai_family == AF_INET && ainfo_ipv4 == NULL) {

+				ainfo_ipv4 = ainfo_iter;

+			}

-		return -1;

+			if (ainfo_iter->ai_family == AF_INET6 && ainfo_ipv6 == NULL) {

+				ainfo_ipv6 = ainfo_iter;

+			}

+		}

+

+		if (ip_version == TOTEM_IP_VERSION_6_4) {

+			if (ainfo_ipv6 != NULL) {

+				ainfo_final = ainfo_ipv6;

+			} else {

+				ainfo_final = ainfo_ipv4;

+			}

+		} else {

+			if (ainfo_ipv4 != NULL) {

+				ainfo_final = ainfo_ipv4;

+			} else {

+				ainfo_final = ainfo_ipv6;

+			}

+		}

+	} else if (ret == 0) {

+		ainfo_final = ainfo;

+	} else {

+		ainfo_final = NULL;

 	}

-	sa = (struct sockaddr_in *)ainfo->ai_addr;

-	sa6 = (struct sockaddr_in6 *)ainfo->ai_addr;

-	totemip->family = ainfo->ai_family;

+	if (ainfo_final == NULL) {

+		if (ret == 0) {

+			freeaddrinfo(ainfo);

+		}

+

+		if (debug_ip_family == 0) {

+			log_printf(LOGSYS_LEVEL_DEBUG, "totemip_parse: IP address of %s not resolvable",

+			    addr);

+		} else {

+			log_printf(LOGSYS_LEVEL_DEBUG, "totemip_parse: IPv%u address of %s not resolvable",

+			    debug_ip_family, addr);

+		}

+

+		return (-1);

+	}

-	if (ainfo->ai_family == AF_INET)

+	totemip->family = ainfo_final->ai_family;

+	if (ainfo_final->ai_family == AF_INET) {

+		sa = (struct sockaddr_in *)ainfo_final->ai_addr;

 		memcpy(totemip->addr, &sa->sin_addr, sizeof(struct in_addr));

-	else

+		debug_ip_family = 4;

+	} else {

+		sa6 = (struct sockaddr_in6 *)ainfo_final->ai_addr;

 		memcpy(totemip->addr, &sa6->sin6_addr, sizeof(struct in6_addr));

+		debug_ip_family = 6;

+	}

-	log_printf (LOGSYS_LEVEL_DEBUG, "totemip_parse: IPv%u address of %s resolved as %s",

+	log_printf(LOGSYS_LEVEL_DEBUG, "totemip_parse: IPv%u address of %s resolved as %s",

 		    debug_ip_family, addr, totemip_print(totemip));

 	freeaddrinfo(ainfo);

-	return 0;

+

+	return (0);

 }

 /* Make a sockaddr_* into a totem_ip_address */

diff --git a/include/corosync/totem/totemip.h b/include/corosync/totem/totemip.h

index de22461..b8da3c9 100644

--- a/include/corosync/totem/totemip.h

+++ b/include/corosync/totem/totemip.h

@@ -1,5 +1,5 @@

 /*

- * Copyright (c) 2005-2010 Red Hat, Inc.

+ * Copyright (c) 2005-2019 Red Hat, Inc.

  *

  * All rights reserved.

  *

@@ -70,8 +70,8 @@ struct totem_ip_address

 enum totem_ip_version_enum {

 	TOTEM_IP_VERSION_4,		/* Use only AF_INET */

 	TOTEM_IP_VERSION_6,		/* Use only AF_INET6 */

-	TOTEM_IP_VERSION_4_6,		/* Use AF_INET and if it fails, use AF_INET6 */

-	TOTEM_IP_VERSION_6_4		/* Use AF_INET6 and if it fails, use AF_INET */

+	TOTEM_IP_VERSION_4_6,		/* Use AF_UNSPEC and filter result preferring AF_INET */

+	TOTEM_IP_VERSION_6_4		/* Use AF_UNSPEC and filter result preferring AF_INET6 */

 };

 struct totem_ip_if_address

diff --git a/man/corosync.conf.5 b/man/corosync.conf.5

index 790f434..0e752bc 100644

--- a/man/corosync.conf.5

+++ b/man/corosync.conf.5

@@ -32,7 +32,7 @@

 .\" * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF

 .\" * THE POSSIBILITY OF SUCH DAMAGE.

 .\" */

-.TH COROSYNC_CONF 5 2018-12-14 "corosync Man Page" "Corosync Cluster Engine Programmer's Manual"

+.TH COROSYNC_CONF 5 2019-01-10 "corosync Man Page" "Corosync Cluster Engine Programmer's Manual"

 .SH NAME

 corosync.conf - corosync executive configuration file

@@ -314,9 +314,11 @@ The value can be one of

 (check only IPv6 address)

 ,

 .B ipv4-6

-(first check IPv4 address, if that fails then look for an IPv6 address) and

+(look for all address families and use first IPv4 address found in the list if there is such address,

+otherwise use first IPv6 address) and

 .B ipv6-4

-(first check IPv6 address, if that fails then look for an IPv4 address).

+(look for all address families and use first IPv6 address found in the list if there is such address,

+otherwise use first IPv4 address).

 Default (if unspecified) is ipv6-4 for knet and udpu transports and ipv4 for udp.

-- 

1.7.1